Effects of Die-Attach Quality on the Mechanical and Thermal Properties of High-Power Light-Emitting Diodes Packaging

Table 2

Thermal resistance of LED packaged with different bonding pressure.

Void fraction	Thickness of die-attach layer (μm)	Thermal resistance of material (calculated) (°C/W)	Thermal resistance of die-attach layer (experiment) (°C/W)	Thermal resistance caused by voids in die-attach layer (calculated) (°C/W)
62.45%	38.8	0.45	2.37	1.95
52.60%	29	0.34	1.63	1.29
39.67%	16.7	0.19	1.12	0.93
29.76%	14.6	0.17	0.81	0.64
16.53%	8.4	0.1	0.41	0.31